And you thought those audio files were only used for music

Such innovations may finally begin to lure big-name advertisers, who are married to such audience statistics. But for now the podcast success story is a rarity.

The most lucrative podcasting marketing deal so far was made several weeks ago. Two moms from Virginia, who began a podcast in March about motherhood, landed a 12-month, $100,000 sponsorship agreement with Dixie paper products. Earlier this year, the condom company Durex paid an undisclosed sum to sponsor The Dawn and Drew Show, an often raunchy podcast recorded in a Wisconsin farmhouse with a loyal audience approaching 200,000.

The issue of finding ways to cash in on podcasting dominated the first ever Portable Media Expo & Podcasting Conference held recently in California. Russell Holliman, who lives in the Heights, was one of just two Houston podcasters who attended the conference.

Todd Spivak

Mary Windham podcasts a show about her sexual
adventures with her husband, Max.

Todd Spivak

Michael and Wendy Chung podcast a quiz show from
their living room in Meyerland.

Holliman founded the Greater Houston Podcasting Association, a nonprofit that tries to match podcasters with local businesses. "Podcasting is a global phenomenon," he says. "People forget about the local aspect of it."

So far, though, few have had any luck landing deals. Holliman says he's frustrated by the lack of activity surrounding podcasting in Houston. As recently as this summer, he says, only a half-dozen podcasts were being made here.

"As is often the case with technology," he says, "Houston is not paying attention."

Up at 5:45 a.m., Mary Windham fixes breakfast and bags lunches, gives her husband a peck good-bye, sends their twin 11-year-old boys off to school and unloads their three-year-old daughter at day care. Then she throws on some scrubs and heads to the dental office a couple of miles away, where she spends the day under fluorescent lights scraping plaque and staving off advances from married men who hope to leave the chair with more than just a cleaning.

The come-ons range from pathetic to pathological. Some men ask if she enjoys inflicting pain. They remark that her husband must be happy to have a woman with such strong hands. A few have invited her over for a quick afternoon romp. "If you'd be my trick, that'd be a treat," one sleazebag told her between rinses a few days before Halloween.

"Some of the girls get uptight about it," Mary says. "I laugh it off."

Mary is careful to keep her private life private. Neither patients nor co-workers know about her alter ego as a late-night sexcaster.

"They think I'm such a Goody Two-shoes," she says with a wink. "They're trying to see if they can embarrass me or shock me, and of course I'm thinking, 'If you only knew, you'd be the one blushing and not me.' "

Mary enjoys her minor celebrity. She's become obsessive about reading e-mails from fans and writing all of them back. She doesn't even mind the occasional bit of hate mail telling her she "shouldn't be allowed" to raise kids. Recently she tried to talk a guy off a ledge who was about to cheat on his wife. Though she has no training, Mary has no qualms about playing the role of therapist.

Her mantra, like that of so many professional sex advisers, is that communication is the key to a healthy sexual relationship. Of course, it doesn't hurt that she's multiorgasmic -- something that her listeners may one day get to witness for themselves. In her podcast about the three-way, she claimed to have climaxed at least 20 times.

"I'm extremely fortunate," she says. "Most of the time I have sex I have multiple orgasms. And that was just a really good day."

While Mary would love to quit her day job and earn a living talking about sex, she's not banking on that ever happening. Rather than seeking advertisers, she's busy trying to come up with new topics. She's already done shows on oral sex, anal sex, lesbian sex and group sex.

In the end, Mary's libido may be stronger than her imagination.

"I don't know if I have that much material," she says. "There's only so much fantasy."